refactor(@angular-devkit/build-angular): remove unused utility files

With the protractor builder removed, these utility functions are no longer used.

Author: clydin

packages/angular_devkit/build_angular/BUILD.bazel

@@ -72,7 +72,6 @@ copy_to_bin(
 RUNTIME_ASSETS = glob(
     include = [
         "src/**/schema.json",
-        "src/**/*.js",
         "src/**/*.html",
     ],
 ) + [

packages/angular_devkit/build_angular/src/utils/index.ts

@@ -8,7 +8,6 @@
 
 export * from './default-progress';
 export { deleteOutputDir, loadProxyConfiguration } from '@angular/build/private';
-export * from './run-module-as-observable-fork';
 export * from './normalize-file-replacements';
 export * from './normalize-asset-patterns';
 export * from './normalize-source-maps';